Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a446f134e140a12…

MALICIOUS

PDF

74.8 KB Created: 2021-09-16 18:53:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 874cc8e13882b4a2717cf6e0618d97fd SHA-1: 234b76e924001c5b34db5c53b2d90eb9d7cd1c83 SHA-256: 4a446f134e140a12c5c30a29de6552d139f09dd18060593b296207827eab9c91
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for delivering malicious content. It also contains numerous external URIs pointing to disposable domains, suggesting a phishing or link-farming operation. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9855

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://infrive.ru/uplcv?utm_term=the+vincent+brothers+pdf
    • http://ekbdrive.ru/ckfinder/userfiles/files/tibafizizuxajij.pdf
    • http://andrenickels.de/ckfinder/userfiles/files/dived.pdf
    • http://algarestofos.pnh.pt/js/ckfinder/userfiles/files/sijixiwetanotebonizumid.pdf
    • http://1mosref.ru/ckfinder/userfiles/files/24963828533.pdf
    • https://cjsc.se/ckfinder/userfiles/files/57879459164.pdf
    • http://www.depomatrial.com/file/71397793862.pdf
    • http://delfosventures.com/userfiles/files/30368107940.pdf
    • http://palyavalaszto.hu/teszt/upload/file/30188602708.pdf
    • http://www.its-dph.cz/admin/fckeditor/editor/userfiles/file/tefexevexeke.pdf
    • https://giolog.biz/images/bulk_images/files/16964342143.pdf
    • https://mcdelandes.ca/uploads/file/wadekubakutanirizavil.pdf
    • http://guowangcable.com/d/files/wifuwumuzemup.pdf
    • http://kronospan-mofa.hu/editor_up/12107246879.pdf
    • http://evergladesharvesting.com/ckfinder/userfiles/files/16153873517.pdf
    • https://bwhe.in/ckfinder/userfiles/files/javufinepekalel.pdf
    • https://www.gico.ge/ckfinder/userfiles/files/tazekunatuvofubulepatuguv.pdf
    • http://acril.ru/ufiles/files/44031804819.pdf
    • https://gagiongvitgiong.com/ckfinder/userfiles/files/zizax.pdf
    • http://holidayservicemarsala.it/userfiles/files/53424123307.pdf
    • http://3dprofi.net/images/uploads/file/82304617222.pdf
    • http://eros-arena.de/eros/userfiles/file/liboluvanopo.pdf
    • http://www.peritaonline.es/ckfinder/userfiles/files/29599157965.pdf
    • https://glasschneider.koeln/wp-content/plugins/super-forms/uploads/php/files/rr7fo092r80f8o40dvvmve2lma/jizexovekisejixag.pdf
    • http://reafamily.lt/ckfinder/userfiles/files/25575367972.pdf
    • http://duhochoangthanh.com/upload/files/82802680427.pdf
    • http://starinviter.com/ckimagefiles/nomuzujevosugi.pdf
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c838.bin
ce47db21d560b1cec50bd17cfd2dc77bdb9361dcf1cb82f107b386882deab26c
pdf-font-stream PDF embedded font (sfnt) at offset 0xC838 16992 bytes
font_01_sfnt_off0000f400.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF400 16792 bytes
font_02_sfnt_off00010c17.bin
f797608f7121f7acd0bd22d49d1022388e81748f838834ffc4f9f73dd640f0a7
pdf-font-stream PDF embedded font (sfnt) at offset 0x10C17 10676 bytes